The U.S. Central Command says Iraqi forces have taken up positions inside one of the world's most important Muslim Shiite shrines in the town of Najaf. A U.S. spokesman says the Iraqis are firing on coalition troops from within the compound, but that allied forces have refused to return their fire.

Brigadier General Vincent Brooks, Central Command's deputy operations director, says a U.S. Army unit that moved into Najaf was fired on from Iraqi forces that had taken up positions inside the Ali mosque compound.

General Brooks says coalition forces chose not to return the fire because they did not want to damage the mosque.

"We can fire back," he said. "We chose not to fire back, and that is a very important distinction. The regime is firing from within a mosque, something that does not have military value, that should be protected by them. It is protected by us."

General Brooks says the Iraqi forces' use of the Ali mosque for military purposes was aimed at triggering a response by U.S. forces. The ploy, in his words, was the latest "detestable example" of the regime's strategy of putting sacred sites in danger. He says coalition troops will continue trying to avoid harming the shrine.